Kenmore hybrid gas water heater error codes

Kenmore hybrid gas water heater code E01, E02

Listed as invalid control board configuration.

Unplug the 120-volt power cord and after 5 seconds, plug it in again. If E01 or E02 reappears, replace the control board. Parts named: control board.

• A one-off configuration error that clears when power is cycled: E01 or E02 appears once after a power interruption and does not return. Unplug the cord for 5 seconds, plug it back in and see whether E01 or E02 comes back
• A control board that has lost or corrupted its configuration: E01 or E02 returns right after the power-cord reset. The chart replaces the control board if E01 or E02 reappears after the reset
• A replacement control board that does not match the water heater: The fault started after a board was fitted and the heater has never run correctly since. Check the part number of the board against the model number on the heater label

The chart's first step for E01 and E02 is to unplug the cord, wait 5 seconds and plug it back in, which makes the control board start over.

Let the heater go through a start-up and a heating call; if the display stays clear the configuration error was a one-off and needs no part.

The chart names the control board as the only part for E01 and E02, so fit a board that matches the model number if the code comes back.

E01, E02 (Kenmore hybrid gas water heater table).

Control board.

A multimeter, a screwdriver or nut driver and a flashlight.

Do E01 and E02 need different fixes? No, the chart gives one procedure for both codes.

Unplug the 120-volt power cord before you touch a harness, connector or part for E01 or E02, and plug it back in only when the step tells you to measure or test

Smell gas at any point while you work on the E01 or E02 fault and you should leave the house and call the gas utility from outside, without touching switches or lighters, since the chart's repairs assume no leak

Kenmore hybrid gas water heater code E03, E04, E05, E06

Listed as main valve relay failure.

Control board detects that a relay used to enable the main valve has failed in either the open or closed position. Replace the control board. Parts named: control board.

• A relay on the control board that failed in the open position: E03, E04, E05 or E06 shows and the main valve never opens. The chart says the control board detected the main valve relay failed open or closed
• A relay on the control board that failed in the closed position: E03, E04, E05 or E06 shows and the main valve stays energized. The chart gives the same fix for open and closed relay failures
• A control board fault that is not a wiring problem: The heater has power and a good ground but still reports the relay failure. The chart lists no other part for E03 to E06, only the control board

The chart groups these four as one main valve relay failure, so record the exact code and whether it repeats for the technician.

With the 120-volt cord unplugged, look at the control board connectors for a loose or burnt terminal before you decide the board itself has failed.

The chart says the control board detects a relay used to enable the main valve has failed open or closed, and its fix for E03 to E06 is to replace the control board.

E03, E04, E05, E06 (Kenmore hybrid gas water heater table).

Do the four codes differ? The chart gives one procedure for all four.

Is there a reset that helps? The chart lists none for these codes, only the board replacement.

Unplug the 120-volt power cord before you touch a harness, connector or part for E03, E04, E05 or E06, and plug it back in only when the step tells you to measure or test

Do not try to jump or bypass the main valve relay for E03, E04, E05 or E06, because the chart's only repair is a new control board

Kenmore hybrid gas water heater code E07

Listed as flame detected.

Flame detected when no flame was expected. Check the flame sensor, flame sensor harness for damage. If the flame sensor and flame sensor harness is okay, replace the control board. Parts named: control board.

• A flame sensor that reports flame when none is present: E07 shows while the burner is off and no flame is visible. Check the flame sensor for damage, as the chart directs
• A damaged flame sensor harness: The harness insulation is worn, wet or shorted along its length. Look at the flame sensor harness for damage along its length
• A control board that reads flame when no flame was expected: The sensor and harness are good and E07 remains. The chart replaces the control board if the flame sensor and harness are okay

The chart says flame was detected when none was expected, so look at the burner first and rule out a real flame before you blame a part.

With the cord unplugged, inspect the flame sensor and the harness that runs from it to the board.

The chart names the control board when both are good; fit one that matches the heater's model number.

E07 (Kenmore hybrid gas water heater table).

Could there be a real flame? Look first; a real flame with the heater off is a gas valve problem for a technician.

If a real flame or heat is visible when the water heater should be off, shut the gas supply and call a technician at once

Unplug the 120-volt power cord before you touch a harness, connector or part for E07, and plug it back in only when the step tells you to measure or test

Kenmore hybrid gas water heater code E09

Listed as high-temperature switch open.

Control board detects that the high-temperature switch is open, preventing power to the main valve. Measure the exhaust gas temperature. High-temperature switch opens when the temperature is 165 degrees, plus or minus 5 degrees, and closes at a temperature of 135 degrees, plus or minus 5 degrees. Check the high-temperature switch with a multimeter to see if it's open or closed. Check the high-temperature switch wire harness and connections for any open or disconnected wires. If the high-temperature switch is open and the water temperature is below 135 degrees, replace the control board. Parts named: high-temperature switch, Control board.

• Exhaust gas that is hotter than the high-temperature switch allows: E09 shows and the exhaust gas measures above 165 degrees F. Measure the exhaust gas temperature; the switch opens at 165 degrees F, plus or minus 5
• A high-temperature switch that is open when the exhaust is cool: The temperature is below 135 degrees F and the switch still reads open. Check the switch with a multimeter: it closes at 135 degrees F, plus or minus 5
• An open or disconnected wire in the high-temperature switch harness: The switch is fine but a connector or wire has come loose. Check the switch wire harness and connections for open or disconnected wires
• A control board that keeps reporting the switch open: The switch and harness are good and E09 remains. The chart replaces the control board if the switch is open and the temperature is below 135 degrees F

The high-temperature switch opens at 165 degrees F, plus or minus 5, and closes at 135 degrees F, plus or minus 5, so the reading tells you whether the switch is doing its job.

With the cord unplugged, test the switch for open or closed and look for open or disconnected wires at its connections.

The chart says if the high-temperature switch is open and the water temperature is below 135 degrees F, replace the control board; the switch and the board are its two parts.

High-temperature switch and control board.

Opens at 165 degrees F, closes at 135 degrees F, each plus or minus 5.

At what temperature does the switch open? 165 degrees F, plus or minus 5; it closes at 135 degrees F, plus or minus 5.

Exhaust gas near 165 degrees F is hot enough to burn, so keep hands and cloth away from the vent while you measure for the E09 fault

Kenmore hybrid gas water heater code E10

Listed as voltage supply too high.

The nominal voltage supply is 120 volts. The over-voltage limit is 132 volts. Check the power cord and wall outlet. Measure the voltage at board connector J7 between pin 1 and pin 3. If the voltage is between limits, replace the control board. Parts named: control board.

• A household supply above the 132 volt over-voltage limit: E10 shows and the outlet measures above 132 volts. Measure the outlet; the nominal supply is 120 volts and the limit is 132 volts
• A damaged power cord or a loose wall outlet: The cord is worn or the outlet is loose and the voltage jumps. Check the power cord and the wall outlet, as the chart directs
• A control board that misreads a good supply: The voltage at connector J7 is within limits and E10 remains. Measure at J7 between pin 1 and pin 3; if it is within limits the chart replaces the control board

The chart's first step for E10 is the cord and outlet; look for damage, burn marks or a loose fit, and measure the outlet, which should be near 120 volts.

Measure between pin 1 and pin 3 of board connector J7: the chart says the nominal supply is 120 volts and the over-voltage limit is 132 volts.

If the supply is between the limits and E10 remains, the chart names the control board as the part to replace.

120 volts nominal, 132 volts over-voltage limit, measured at J7 pin 1 to pin 3.

What should the supply be? 120 volts nominal; 132 volts is the over-voltage limit.

Where do I measure it? At board connector J7, between pin 1 and pin 3.

Measuring voltage at board connector J7 means working near live wiring, so have an electrician or a technician do it if you are not trained for the E10 check

Kenmore hybrid gas water heater code E11

Listed as voltage supply too low.

The nominal operating voltage is 120 volts. If the voltage supply is below the limit of 102 volts at the outlet, call an electrician., Check the power cord and wall outlet connections., Measure the voltage at board connector J7 between pin 1 and pin 3. If the voltage is between limits, replace the control board., Parts named: control board.

• A household supply below the 102 volt limit at the outlet: E11 shows and the outlet measures under 102 volts. Measure the outlet; the nominal supply is 120 volts and the low limit is 102 volts
• A poor connection at the power cord or wall outlet: The cord plug is loose or the outlet is worn and the voltage sags. Check the power cord and the wall outlet connections, as the chart directs
• A control board that misreads a good supply: The voltage at connector J7 is within limits and E11 remains. Measure at J7 between pin 1 and pin 3; if it is between limits the chart replaces the control board

The chart says the nominal operating voltage is 120 volts and that a supply below 102 volts at the outlet needs an electrician.

Look for a loose plug, a scorched outlet or a damaged cord that could drop the voltage under load.

Measure between pin 1 and pin 3 of connector J7; if the voltage is between the limits and E11 remains, the chart replaces the control board.

120 volts nominal, 102 volts low limit, measured at J7 pin 1 to pin 3.

If the outlet measures below 102 volts, call an electrician, since a supply problem is a household wiring problem and not a water heater part

Kenmore hybrid gas water heater code E12, E13, E14

Listed as abnormal blower current.

Check for a blocked or restricted exhaust vent.

Follow the venting installation instructions in the owner's manual. If the venting system is clear, recalibrate the unit following the procedure in the owner's manual. If it continues to display the error, replace the blower. Replace the control board. Parts named: blower, Control board.

• A blocked or restricted exhaust vent: E12, E13 or E14 shows and the blower strains or the vent is obstructed. Check the exhaust vent for a blockage and follow the venting installation instructions
• A blower that needs recalibrating after a vent change: The vent is clear but the current reading is off. Recalibrate the unit with the procedure in the owner's manual
• A failing blower motor: The vent is clear and the code returns after recalibration. The chart replaces the blower if the error continues
• A control board that reads the blower current wrongly: A new blower is fitted and the code still does not clear. The chart also lists the control board as a replacement

Follow the venting installation instructions in the owner's manual; the chart begins with the vent because a restriction raises the blower current.

The chart says to follow the calibration procedure in the owner's manual, which resets the reference the control uses for the blower reading.

The chart names the blower first and the control board second for E12, E13 and E14.

E12, E13, E14 (Kenmore hybrid gas water heater table).

Blower and control board.

Do not run the heater with a blocked exhaust vent for the E12, E13 or E14 fault, because combustion gases must leave the house

Smell gas at any point while you work on the E12, E13 or E14 fault and you should leave the house and call the gas utility from outside, without touching switches or lighters, since the chart's repairs assume no leak

Kenmore hybrid gas water heater code E15, E16, E17, E18, E19

Listed as abnormal blower speed.

Unplug the water heater and check the blower wire harness. If the wire harness is okay, replace the blower. If it continues to display the error, replace the control board. Parts named: blower, Control board.

• A damaged or loose blower wire harness: E15, E16, E17, E18 or E19 shows and the blower speed is not reported correctly. Unplug the water heater and check the blower wire harness
• A blower that does not reach or hold its speed: The harness is good and the blower is slow, noisy or stuck. The chart replaces the blower if the wire harness is okay
• A control board that misreads the blower speed: A new blower is fitted and the code still does not clear. The chart replaces the control board if the error continues

The chart's first step for the five speed codes is the harness that carries the blower's power and speed signal, so look for a loose or damaged connector.

The chart names the blower as the next part; the wheel and motor together are replaced as one part.

If a new blower does not clear the code, the chart calls for the control board.

E15, E16, E17, E18, E19 (Kenmore hybrid gas water heater table).

Blower and control board.

What do E15 to E19 mean on a Kenmore hybrid gas water heater? Abnormal blower speed, in the chart's words.

Unplug the 120-volt power cord before you touch a harness, connector or part for E15, E16, E17, E18 or E19, and plug it back in only when the step tells you to measure or test

Smell gas at any point while you work on the E15, E16, E17, E18 or E19 fault and you should leave the house and call the gas utility from outside, without touching switches or lighters, since the chart's repairs assume no leak

Kenmore hybrid gas water heater code E20, E21

Listed as proportional valve.

The proportional valve current is either too low or too high. Check the gas valve and wire harness for any damage. Replace the control board. Replace the gas valve assembly. Parts named: control board, Gas valve assembly.

• A proportional valve current that is too low: E20 or E21 shows and the valve is not opening as far as the control expects. The chart says the current is either too low or too high, without saying which code is which
• A proportional valve current that is too high: E20 or E21 shows and the valve is drawing more than the control expects. Check the gas valve and its wire harness for any damage
• A damaged gas valve wire harness: The harness insulation is worn or a pin has backed out. Check the wire harness for damage before you replace the valve
• A control board or gas valve assembly that has failed: The harness is good and the code returns after a reset. The chart lists the control board and the gas valve assembly as the replacements

The chart says the proportional valve current is either too low or too high, so look at the connector and the wires before you replace the valve.

The chart lists the control board first for E20 and E21, since the board supplies the valve current.

If the board does not clear it, the chart names the gas valve assembly; this part is best fitted by a qualified technician.

Control board and gas valve assembly.

The gas valve assembly is part of the gas train, so leave replacing it for E20 or E21 to a qualified gas technician

Smell gas at any point while you work on the E20 or E21 fault and you should leave the house and call the gas utility from outside, without touching switches or lighters, since the chart's repairs assume no leak

Kenmore hybrid gas water heater code E23

Listed as shorted water outlet temperature sensor.

The control board detected a shorted water outlet temperature sensor (thermistor) or thermistor wire circuit. Check the temperature sensor wire harness and connections for any damaged or broken wires. If the temperature sensor and wiring is shorted, replace the temperature sensor. If the sensor and sensor wire circuit is not shorted, replace the control board. Parts named: outlet temperature sensor, Control board.

• A shorted wire in the outlet sensor harness: E23 shows and the outlet temperature circuit reads shorted. Check the temperature sensor wire harness and connections for damaged or broken wires
• An outlet temperature sensor (thermistor) that has shorted: The wiring is fine and the sensor circuit measures as a short. Replace the outlet sensor if the sensor and wiring are shorted, as the chart directs
• A control board that misreads a sensor that is not shorted: The sensor and its wire circuit are not shorted and E23 remains. The chart replaces the control board if the sensor circuit is not shorted

The chart says the control board detected a shorted water outlet temperature sensor or thermistor wire circuit, so look for pinched or damaged wires first.

With the cord unplugged, check the sensor circuit with a multimeter; a shorted reading means the chart replaces the sensor.

The chart replaces the control board when the sensor and sensor wire circuit are not shorted.

Outlet temperature sensor and control board.

How do I tell which part failed? If the sensor and wiring measure shorted, replace the sensor; if not, the control board.

Hot water pipes at the outlet can scald, so let the heater cool before you reach for the outlet sensor for E23

Kenmore hybrid gas water heater code E24, E25

Listed as inlet temperature sensor.

The control board detected a shorted or open inlet temperature sensor (thermistor) or thermistor wire circuit. Check the temperature sensor wire harness and connections for any damaged or broken wires. If the temperature sensor and wiring is shorted, replace the temperature sensor. If the temperature inlet sensor and sensor wire circuit is not shorted or open, replace the control board. Parts named: inlet temperature sensor, Control board.

• A shorted or open wire in the inlet sensor harness: E24 or E25 shows and the inlet temperature reading is missing. Check the temperature sensor wire harness and connections for damaged or broken wires
• An inlet temperature sensor (thermistor) that is shorted: The wiring is fine and the sensor circuit measures shorted. Replace the temperature sensor if the sensor and wiring are shorted, as the chart directs
• An inlet temperature sensor that is open: The sensor circuit reads open with the harness intact. Check the sensor circuit for an open reading with a multimeter
• A control board that misreads a good inlet sensor: The inlet sensor and its wire circuit are not shorted or open and the code remains. The chart replaces the control board if the inlet sensor circuit is neither shorted nor open

The chart says the control board detected a shorted or open inlet temperature sensor or its wire circuit, so look for damaged or broken wires first.

With the cord unplugged, check for a shorted or open reading; a shorted sensor and wiring means the chart replaces the temperature sensor.

If the inlet sensor and its wire circuit are good and E24 or E25 remains, the chart names the control board.

Inlet temperature sensor and control board.

Do E24 and E25 differ? The chart gives one procedure for both codes.

Water at the inlet can be hot after a heating cycle, so let the heater cool before you reach for the inlet sensor for E24 or E25

Kenmore hybrid gas water heater code E26, E27

Listed as tank temperature sensor.

The control board detected a shorted or open tank temperature sensor (thermistor) or thermistor wire circuit. Check the tank temperature sensor wire harness and connections for any damaged or broken wires. If the tank temperature sensor and wiring is shorted, replace the tank temperature sensor. If the tank temperature sensor and sensor wire circuit is not shorted or open, replace the control board. Parts named: tank temperature sensor, Control board.

• A shorted or open wire in the tank sensor harness: E26 or E27 shows and the tank temperature reading is missing. Check the tank temperature sensor wire harness and connections for damaged or broken wires
• A tank temperature sensor (thermistor) that is shorted: The wiring is fine and the sensor circuit measures shorted. Replace the tank temperature sensor if the sensor and wiring are shorted, as the chart directs
• A tank temperature sensor that is open: The sensor circuit reads open with the harness intact. Check the sensor circuit for an open reading with a multimeter
• A control board that misreads a good tank sensor: The tank sensor and its wire circuit are neither shorted nor open and the code remains. The chart replaces the control board if the tank sensor circuit is neither shorted nor open

The chart says the control board detected a shorted or open tank temperature sensor or its wire circuit, so look for damaged or broken wires first.

With the cord unplugged, check for a shorted or open reading; a shorted sensor and wiring means the chart replaces the tank temperature sensor.

If the tank sensor and its wire circuit are good and E26 or E27 remains, the chart names the control board.

Tank temperature sensor and control board.

Do E26 and E27 differ? The chart gives one procedure for both codes.

Water in the tank can scald, so let it cool before you reach for the tank sensor for E26 or E27

Kenmore hybrid gas water heater code E28

Listed as ignition failure.

The control board failed to detect the flame during ignition. The control will retry a number of times to detect the flame. After the maximum failed attempts, this fault will display. Unplug the water heater and check the igniter wire harness for any damage or loose connections. Check the ignition rod. If it looks dirty, clean it using isopropyl alcohol and a clean cloth. Check the high voltage wiring connection between igniter and igniter rod for proper contact.

• A damaged or loose igniter wire harness: E28 shows after the control tried to light the burner several times. Unplug the water heater and check the igniter wire harness for damage or loose connections
• A dirty ignition rod: The rod looks sooty or coated and the flame never establishes. Clean the ignition rod with isopropyl alcohol on a clean cloth if it looks dirty
• A poor high voltage connection between the igniter and the igniter rod: The lead is loose or corroded where it meets the rod. Check the high voltage wiring between the igniter and the igniter rod for proper contact

The chart says the control board failed to detect the flame during ignition after the maximum number of retries, so look for damage or loose connections.

The chart says to use isopropyl alcohol and a clean cloth, with the heater unplugged and cool.

Make sure the lead sits firmly on the rod and shows no burn or corrosion; the chart lists no part for E28 beyond these checks.

None; checks only.

Isopropyl alcohol, a clean cloth, a screwdriver and a flashlight.

How do I clean the ignition rod? With isopropyl alcohol and a clean cloth.

Does the chart name a part? No, E28 lists checks only.

Smell gas at any point while you work on the E28 fault and you should leave the house and call the gas utility from outside, without touching switches or lighters, since the chart's repairs assume no leak

Kenmore hybrid gas water heater code E30

Listed as blower.

Check the blower motor and blower wheel.

Check the venting system and confirm the blower wheel turns freely and is not stuck. Check the blower wire harness connections. Replace the blower motor. Replace the control board. Parts named: blower motor, Control board, Blower motor wire harness.

• A blower wheel that is stuck or rubbing: E30 shows and the blower does not turn freely. Check that the blower wheel turns freely and is not stuck
• A restricted venting system: The wheel is free but the vent is blocked or crushed. Check the venting system for a blockage or restriction
• A loose blower wire harness connection: The blower is silent and a connector is out of its socket. Check the blower wire harness connections for a loose plug
• A failed blower motor or control board: The wheel, vent and harness are good and E30 remains. The chart replaces the blower motor, then the control board

The chart starts with the wheel turning freely and the vent being clear, since either one can stop the blower.

Look for a loose, pushed-out or damaged connector between the blower motor and the control board before you replace anything.

The chart names the blower motor, the control board and the blower motor wire harness as its parts for E30.

Blower motor, control board and blower motor wire harness.

Kenmore hybrid gas water heater code E33

Listed as water flow valve.

The water valve did not open when attempting to establish flow. Check the water valve, wire harness and connections. Replace the water valve. Replace the control board. Parts named: control board, Water valve.

• A water valve that did not open when the heater tried to establish flow: E33 shows and no water moves through the heater at start-up. The chart says the water valve did not open when attempting to establish flow
• A damaged water valve wire harness or a loose connection: The connector at the water valve is loose or corroded. Check the water valve, its wire harness and connections
• A failed water valve: The harness is good and the valve never opens. The chart replaces the water valve if the checks are good
• A control board that does not drive the valve: A new water valve is fitted and the code still does not clear. The chart lists the control board as the other replacement

The chart says the water valve did not open when attempting to establish flow, so check the valve and its connector for damage first.

The chart names the water valve as the part to replace after the checks; shut off the water supply first.

The chart lists the control board as the second part for E33, after the water valve has been replaced.

Water valve and control board.

Turn off the water supply before you remove the water valve for E33, or the tank piping will flood the area

Kenmore hybrid gas water heater code E34

Listed as proportional gas valve.

The proportional gas valve is not functioning properly. Check the gas valve wire harness and connections. Replace the control board if the wire harness and connections are okay. Parts named: gas valve assembly, Control board.

• A damaged gas valve wire harness: E34 shows and the proportional gas valve does not respond. Check the gas valve wire harness and connections for damage
• A loose connection at the gas valve: A connector at the gas valve has worked loose over time. Check the gas valve wire connections and seat them firmly
• A control board that does not drive the gas valve: The harness and connections are okay and E34 remains. The chart replaces the control board if the wire harness and connections are okay

The chart says the proportional gas valve is not functioning properly, so look for damage and loose connectors on the valve harness.

The chart replaces the harness first when it is damaged, which keeps the gas train itself untouched.

The chart names the control board as the next part; the gas valve assembly is also listed as a part for E34.

Gas valve assembly and control board.

Kenmore hybrid gas water heater code E35

Listed as repeated flame loss.

Flame is going out due to low gas pressure or a low flow rate. Clean or change the water filter. Check the flame sensor wire harness and wire connections. Clean the flame sensor if it looks dirty. Have the gas pressure measured. Replace the flame sensor. Replace the control board. Parts named: water filter, Flame sensor, Control board.

• A water filter that is clogged: E35 shows and the flame keeps going out during a heating cycle. Clean or change the water filter, as the chart directs
• A dirty flame sensor: The sensor looks sooty and the flame is lost repeatedly. Clean the flame sensor if it looks dirty
• A loose flame sensor wire harness or connection: The connector at the sensor is out of place. Check the flame sensor wire harness and wire connections
• Low gas pressure or a low flow rate: The flame goes out because the gas supply is weak. Have the gas pressure measured by a gas technician
• A failing flame sensor or control board: The filter, sensor and gas pressure are good and E35 remains. The chart replaces the flame sensor and then the control board

The chart lists the water filter first for E35, since a restricted flow changes the flame and lets it go out.

Check the wire harness and connections, and clean the flame sensor if it looks dirty.

The chart says low gas pressure or a low flow rate lets the flame go out, then names the flame sensor and the control board as replacements.

Water filter, flame sensor and control board.

Who measures gas pressure? A gas technician, since it is measured at the gas train.

Kenmore hybrid gas water heater code E36

Listed as calibration error.

Calibration sequence incomplete or dip switch 4 is not set to the proper setting. Unplug the water heater and then check dip switch 4 and put it in the ON position. Follow the instruction in the use and care guide for the calibration procedures. Parts named: control board.

• A calibration sequence that did not finish: E36 shows after a calibration was started and interrupted. Follow the calibration procedure in the use and care guide from the start
• Dip switch 4 that is not in the ON position: The control board dip switch 4 is set to OFF. Unplug the water heater and check that dip switch 4 is in the ON position
• A control board that needs replacing: The dip switch is ON and the calibration was completed but E36 remains. The chart names the control board as the part for E36

The chart says the calibration sequence is incomplete or dip switch 4 is not at the proper setting, so put dip switch 4 in the ON position.

The chart directs you to the use and care guide for the calibration instructions; complete every step without interrupting it.

The chart names the control board as the part for a calibration error that survives both checks.

Where do I set dip switch 4? In the ON position, with the water heater unplugged.

Where is the calibration procedure? In the use and care guide, per the chart.

Kenmore hybrid gas water heater code E37

Listed as no water flow.

The heater could not start because the water flow was not established caused by an air bubble or a blockage in the water passage, a failed flow sensor or faulty circulation pump. Turn on a hot water faucet to purge air from the tank. Verify the cold water supply to the water heater is turned on and that the circulation pump operates. Check the circulation pump and wire harness connections. Clean or replace the water filter. Replace the control board. Replace the circulation pump. Replace the water valve. Parts named: water filter, Circulation pump, Water valve.

• An air bubble in the water passage: E37 shows on a first start after the tank was drained or refilled. Turn on a hot water faucet to purge air from the tank
• A cold water supply that is turned off: No water reaches the heater and E37 shows at start-up. Verify the cold water supply to the water heater is turned on
• A clogged water filter: The filter is packed with debris and the flow is low. Clean the water filter or replace it if it is packed with debris
• A circulation pump that does not run, or its wire harness: The pump is silent or a connector is loose. Check that the circulation pump operates and that its wire harness connections are secure
• A failed water valve or control board: The pump and filter are good and E37 remains. The chart replaces the control board, the circulation pump and the water valve

The chart says the heater could not start because water flow was not established, so turn on a hot water faucet to purge air from the tank and verify the cold water supply is on.

Verify the circulation pump operates, check its wire harness connections and clean or replace the water filter.

The chart lists all three, in that order, when the flow still cannot be established after the purge and the checks.

Water filter, circulation pump and water valve.

What can cause it? An air bubble or a blockage in the water passage, a failed flow sensor or a faulty circulation pump.

Turn off the water supply before you remove the water filter, circulation pump or water valve for E37, or the piping will flood the area

Kenmore hybrid gas water heater code E99

Listed as control board.

Faulty control board. Replace the control board. Parts named: control board.

• A control board that has failed: E99 shows and no other code explains the fault. The chart calls E99 a faulty control board
• A power surge that damaged the control board: E99 appeared after a storm or a household power event. Ask whether the fault started after a power event in the house
• A loose or corroded connector on the control board: The board looks fine but a plug has worked loose. Unplug the heater and reseat the connectors before you buy a board

The chart gives no test for E99, so rule out a loose connector on the board before you replace it.

Plug the cord back in and watch the display; a code that comes back at once points to the board itself.

The chart's fix for E99 is to replace the faulty control board; fit one that matches the model number.

Is there a test for E99? The chart lists none; it goes straight to replacing the board.

Could a power surge cause it? It is a common cause of a failed board, but the chart does not say so.